Reinforcing-bar.



.Pi-1 KALM\AN. REINFoRcmG an'. ,APPLICATION HL'IEIJ Mula. Ism

Patented sept. 3,1918,

citizen of the 1t is UNITED STATES PATENT oEEioE. i

PAUL J. KALMAN, OF ST. RAUL, MINNESOTA.

REINFOBCING-BAE.

Continuation of application Serial No. 185,418, tiled August 10, 1917. This application filed )lay 13, 1918. l

Specification of Letters Patent.

Patented sepas, 191s.

Serial No. 234,143.

To all lwhom it may concern:

' Be it known that I, PAUL J. KALMAN, a. United States, and resident of St. Paul, in the county ot Ramsey and State of lVIin1iesota, ha\*e invented certain new and useful improve-,ments in lteintorcingliars, oit' which the following is a specification.

This application relates to reinforcing bars ior concreto and is a continuation of my @impending ailiplii'zation Serial No. 185,418, tiled August 1 0, '1917.

dcsiral'ilo that reinforcing hars, vWhether round or rectangular in cross seo-e tion, shall he provided with directly transverse ribs. Attempts have been made here toi'ore to roll a hai having such ribs but in no instance has it been found possible to torni the ribs without distortion of sonic portion thereof. This iu itseltis 'objectionablein that it reduces the bonding,r capacity ot the bai', but an 'ibjection equally great is that udistortion of the ribs implies unnecessary Weill' f lnd i'flllll {.letei'ioration ot' the rolls and the consumption ot' inorepower in the rol ling operation-than would be necessary if the liar were correctly designed.

4 To that end therefore l have designed a bar which may be rolled without distorting the ribs, with consequent advantages. 1t will be understood that reinforcing ineinbers sla-li as eonnuonly used today are foi'niedby passing a heated bar between a pair of rolls, one-halt of the pass being contained in cach roll.- The bar which is fed into the rollsis of anywhere from Q5 to 35% larger cross sectional area than thatot the bar which issues from the pass.. This is necessary in order that there will be slitticient material to fill the grooves in the roll and forni the ribs on the bar. It will be Hundeifstood also that the grooves which moif'enient of the bar.

fiat a point coincident with aline intersecting the axes of the twojrolls; .furthermore that the angularity between the grooves and the rib :formed thereby increases with .the angularity of the roll due to the` tangential oiI redin tion.

vtaoe or Wall of the rib :may

The difficulties a1'is,

ing from this fact are increased due tothe tact that the reduction in size of the bar implies and necessitates a corresponding elonration ot therbai; that is, theoretically if there is a 25% reduction on the bar inthe rolls, the bar should issue from the rolls 251%; faster than `it enters. found that the elongation of lthe formed bar as it emerges from the roll is proportional to the aniount of reduction, and is ap proximately 4 to 5% in excess of the speed of the periphery of the rolls at approximately 50% reduction. The reduction necessary depends on the width and depth ol the ribs, and the-lead ot' the bar over the peripheral speed ot' the rolls depends on4 the amount The etl'ect of the increasing between the groove in the roll an g ul a ri ty yand the rib on the bar and the increase in .speed of' travel of the rib over the peripheral .speed of the roll results in wiping oi or distort-ing,r the portion of the rib whichis not freed from the roll.v A rib constructed as described herein will not be distorted and will be freed from the roll Without conflict therewith.

l have found that with a rib disposed transversely thereof', one be substantially vertical and this is'an important advantage due to the increased bondingr capacity. have 'found also that by inclining the oppo; site of the rib in a certain manner with relation to the height of the rib, the liability to distortion is eliminated, The proper angle is approximately. 45 Ato the longitudinal axis of the har, the anOle vary ing somewhat with the height ot'wtlniy rib.

by designing the bar It has been at least as great it not ngreater .than the 4 height of the rib.

The invention will be more readily nii-j.4

derstood by reference drawings, wherein;

Figure 1 is a transverse to .they accompanying' Section through a 'pair of'rolls showing a reinforcing bar `in the process of formation in the pass; y

Fin'` 2 is a sectionai 4Vie-W on the line "2f-2 f of Fig. 1; y y y Fig. 3 is a fragfiner'itary sectional View onv the vline 3-3 lof Fig. 1;

Figs. 4, 5, 6 and 7 are plan views showing the groove in the roll in its relative pose tion to the rib on the bar at different points in the progress of the bar, and,

Figs. 8, 9, -10 and 1l are sectional views through the roll and bar, taken in the posi tion of the parts in Figs. 4 to 7 inclusive, the 'views beingl on the lines 8i-8, 9--9, lOl() and 11--11 respectively of Figs. 4 to The bar is shown as being generally rectangular in outline although it may be made round 'it desired. It is preferably provided with a main or body portion 10, having four diametrically opposed longitudinally extending corner ribs 11. The longitudinal ribs are joined by directly transverse ribs 12, one face 13, of which is substantially perpendicular to the longitudinal axis of the bar while the other face 14, is inclined' at an angle substantially 450 to-the said axis of the bar.

I'n' order to produce a bar such as described it is received in the pass formed by peripherally grooving two rolls 15, 16, one half of the pass being formed in each roll. lhe peripheral grooves ot the roll are transversely grooved as at 1T, in order to properly shape. the, rib on the bar. lt has been found in practice that due to the elongation ofthe liar, the distance between adjacent ribs 12, on the bar is greater by l to 5"() than the distance between adjacent grooves 17, on the roll and this, when taken in eonnection with the peculiar angular relation ofthe. parts due to the, tangential movement of the Jar, causes the portions i8, of the rib (best shown in l4`ig. 3) to be wiped ottl or distorted, the distortion being greatest at the `point indicated and being lessened to a point extending to nearly the end of Ythe rib. I have discovered that by designing the rib as described herein its distortion may be avoided. 'lhe reason t'or such design is illustrated in Figs. 3 to 1l inclusive. In these figures it will be seen that the groove 17, inthe roll immediatel)r on leaving the central position at which the rib is formed begins to more angularly away7 from the formed rib, but as the, longitlulilud axis of the groove. is always radial to the. roll and as the longitudinal axisof thefor-med rib is always perpendicular to thel 'longitudinal axis of the tangentially moving bar, the tendency is for the rib to be caught in the groove, particularly when it is borne in `mind that the, .speed ot travel ot' the bar 1s increased over the peri|')hera`il speed of the, roll. ln Fig. 11 I have. indicated in dotted lines a triangle whose hypotenuse. Il), is the incline on the rib and whose. altitude 20, is the height of the rib. The length of the base 213 therefore controls tlnl angle 19, and in the appended claims the base 21, of the trianglethus formed is indicated as being of greater length than the height of the rib. hisimplies that the angle 19'tshall be less `than 45". This angle may bg lessened if '`desired, but the figures illustrate that this is approximately the extreme angle which may be employed for rolling a ribfwithout distortion. The dot and dash lines indicate an intermediate position in Fig. 1, and are shown for the purpose of illustrating, asin Fig. 3, the manner in which the groove is inbe'ect twisted with relation vto the formed r1 The bar herein illustrated possesses material advantages in that it may be formed as shown. Other bars have been illustrated and described having ribswhieh ma form an equally efficient bond but such ri scannot be rolled and the reason therefor will be apparent from the foregoing description. The vertical face of the rib provides an extremely etticient abutment. for the cementitions material.

It will be understood, of course, that the ideas here expressed and the difficulties encountered in rolling the bar arc the same whether the bar is reetangldar or rounder intermediate of shapes.

I claim: y

1. A reinforcing member for concrete comprising a bar having spaced direct-l transverse ribs thereon one face of eac'h ri being substantially perpendicular to the longitudinal axis of the bar and the other face of 'each rib being inclined substantially 450, substantially as described.

2. A reinforcing member for concrete comprising a bar having spaced transverse ribs thereon, one face of the ribs being substantially perpclnlicular to the longitudinal axis ot' the bar and the other face being inclined, the incline constituting the hypotenuse of a triangle. whose base has a length at. least as great as the height of the rib, substantially as described.

3. A rolled deformed bar having a transverse rib provided with a face at substann tially right angles to the lon itudinal-axis of the bar, the opposite face ci; the yrib being materially inclined outwardly toward the tirst mentioned face to give clearance in the forming rolls.

4; A rolled 'deformdd barhaving' a portion provided with a pluralityl of continuous transverse ribs surrounding the bar, one face of each of the transverse ribs being substantially l)erpeudieular to the longitudinal axis of the bar, the opposite face of each of the said ribs` being materially inclined outwardly toward the first mentioned face of the rib.

5. A reinforcing member comprising a bar having a body vided with a plurality of space for concrete, gortlon protransverse body` ribs substantially surrounding the bnr, one with said first mentioned face of thu rib by face of each of the trul'isverse ribs being Sub a, fiat part.

stantially perpendicularto the longitudinal Sigl'ied :1t St. Paul, Minnesota, this 10th 10 axisof the bm', and the opposite fame of auch day of Muy, 1918. 5 of said ribs being materially inclined from PAUL J. KALMAN.

thebase thereof outwardly toward the first Witness: mentioned fain@ oi the rib, and connecting A. E. PINARD. 

